1. Field of the Invention
The present invention relates to an IC card connector device incorporated in an apparatus that is used with an IC card inserted therein and extracted therefrom, and more particularly, to an ejection mechanism for ejecting an IC card in a loaded state.
2. Description of the Related Art
A general type of IC card connector device roughly comprises a pin header section in which a large number of pin contacts to be connected to socket contacts in an IC card are arranged in a pin housing, a frame for guiding the IC card during insertion and extraction, an ejection mechanism for disconnecting the loaded IC card from the pin contacts, and the like. In another known type of connector device, the pin housing and the frame are molded in one piece.
Conventionally, an ejection mechanism is widely used that includes a pushrod held on the outer side face of the frame to reciprocate in the IC card inserting and extracting direction, and an ejection lever pivotally supported on the frame or the pin housing and engaged at one end with the pushrod. In a connector device having such an ejection mechanism, when the pushrod is pushed in the state in which the IC card is loaded, a protruding piece of the ejection lever pivots in relation to the pushrod, thereby pushing the IC card frontward to the position where the IC card is allowed to be easily pulled out by the fingers. However, since the pushrod is projecting frontward when the IC card is loaded, it may be misoperated or suffer impact, and the IC card may be ejected unexpectedly. In this case, the IC card is disconnected, and trouble arises, for example, operation data is lost.
In contrast, an IC card connector device disclosed in Japanese Unexamined Utility Model 6-13072 comprises first and second transmission levers for linking a pushrod and a slide plate, a third transmission lever supported by the first transmission lever so as to be engaged with and disengaged from the second transmission lever, and a heart-shaped cam mechanism that is able to hold the pushrod in a predetermined retracted position and a first projecting position. The amount of depression of the pushrod is selectively transmitted to the slide plate in accordance with the amount of projection of the pushrod. That is, while an IC card is loaded, the third transmission lever is not engaged with the second transmission lever, and the pushrod is held in the retracted position where it is depressed by a predetermined amount. When the pushrod is projected to the first projecting position by the heart-shaped cam groove and is then further pulled to a second projecting position, the third transmission lever is engaged with the second transmission lever at the second projecting position. When the pushrod is pushed to the retracted position in this state, the pushing force is transmitted to the slide plate via the transmission levers, and the slide plate pushes and ejects the IC card frontward. Therefore, in this IC card connector device, while the IC card is connected, the pushrod is held in the retracted position where it is not projecting frontward. Only in ejecting the IC card, the pushrod is projected to the second projecting position, and is then pushed in. This can prevent the IC card from being disconnected due to a misoperation of the pushrod or the like.
As described above, in the disclosed IC card connector, the pushrod can be held in the predetermined retracted position while the IC card is connected. Therefore, it is possible to prevent the IC card from disconnection that may be caused when the pushrod is misoperated or suffer impact in the depressing direction. Since the pushrod must be projected to the second projecting position in order to eject the IC card, even if the pushrod is inadvertently projected to the first projecting position although the IC card need not be ejected, it can be returned to the retracted position without ejecting the IC card, by pushing the pushrod from the first projecting position without pulling it to the second projecting position. According to the above-described structure, for example, even when a lower pushrod is pushed instead of an upper pushrod by mistake in an IC card connector device capable of containing two IC cards, such a misoperation does not become serious, and the ejecting operation can be performed safely.
In such a conventional IC card connector device, however, the force for pushing the pushrod is transmitted to or cut from the slide plate in accordance with the positions of three transmission levers that are linked between the pushrod and the slide plate. This needs a sufficiently wide space to pivot the transmission levers therein, and hinders the size reduction of the IC card connector device. Furthermore, for this reason, the transmission levers must be placed on the top side or bottom side of an IC card insertion slot. In particular, in the case of a multiple IC card connector device that is able to load or unload two or more IC cards, since there is a need to vertically stack a plurality of pairs of transmission levers in a sufficient space, the IC card connector device is also enlarged in the height direction. Furthermore, such a conventional IC card connector device needs three operations in a normal ejecting operation: an operation of projecting the pushrod to the first projecting position by pushing the pushrod held in the retracted position; an operation of pulling the pushrod in the first projecting position to the second projecting position; and an operation of pushing the pushrod projected in the second projecting position into the retracted position. This makes the ejecting operation troublesome. Moreover, since the IC card ejecting operation is performed after the pushrod is projected to the second projecting position via the first projecting position, the two operations of projecting the pushrod are apt to be performed in succession. For this reason, there is a fear that the pushrod will be inadvertently projected to the second projecting position, and that it cannot be returned to the initial position without ejecting the IC card.